Abstract: Implantable electrodes adapted to interact with electrically excitable tissue are selected by an implantable, programmable controller that receives power from a main cable and data from a data conductor that identifies the stimulation and recording electrodes to be activated. The implantable controller enables electrical signals to be transmitted between a distal site of power generation and a selected subset of multiple electrodes with a minimum number of conductor wires.

Abstract: A transcutaneous medical electrode includes a highly conductive grid, having a plurality of arrays of electrical conductors, for controlling current distribution of directed electrical pulses. Electrical connectors are provided for establishing electrical communication with the conductive grid for enabling selective electrification of the electrical conductors in each array. The conductive grid is supported by a moderately conductive sheet, or film, and a conductive adhesive is provided for removably coupling the sheet or film and the conductive grid to a user's body.

Abstract: A flexible, lightweight, inexpensive, and easy to attach sensor mask (10) for placement on a patient (11) for monitoring physiological signals of the patient is disclosed. The sensor mask includes an elongated flexible substrate (12); a plurality of electrodes (14) spaced along the length of the substrate and configured for placement against the patient for sensing the physiological signals; and at least one electrical connector (16) electrically coupled with the electrodes for delivering the physiological signals sensed by the electrodes to a recording/analyzing device. The electrodes are formed of patches of conductive ink that are deposited on the substrate at spaced locations along the length thereof. The electrical connector includes terminals formed of conductive ink deposited on the substrate and is electrically coupled with the electrodes by a plurality of lines of conductive ink deposited on the substrate.

Abstract: An array of electrodes is constructed to allow the user to easily adjust to the correct size of the patient's head. The array is self-adhesive, pre-gelled and disposable. The array fits easily over the temple and forehead areas where EEG signals can be acquired by specially designed monitors for purposes of monitoring a number of bodily phenomena, including but not limited to, depth of anesthesia, and/or ischemia, and burst suppression. The array is connected to the monitor via a tab connector that is integral to the disposable device. The tab connector is insertible into a reusable connector that is part of a monitoring system.

Abstract: A leadwire harness system is used for recording an electrocardiogram (ECG) during magnetic resonance imaging (MRI). The system includes a set of leadwires each having a nichrome wire helically wound on a bundle of glass or other high strength fibers and surrounded by an insulating jacket to provide for uniformly distributing the high resistance within each leadwire so that the eddy currents generated by the rapidly changing magnetic field are greatly reduced. The set of leadwires are twisted within a surrounding tube of foam insulation. The reduction of the eddy currents dramatically reduces MRI image distortion as well as the potential for localized heating and skin burns under the ECG electrodes used with the harness system.

Abstract: Disclosed is an electrode array (i.e., "sensor") and a method for separating near and far-field signals. In one embodiment a horizontal array is used, and in an alternate embodiment a vertical array is used. The electrode array consists of two well-separated pairs of closely spaced electrodes (and a separate ground element). In a typical application of collecting a channel of EEG, "sensing" electrodes are placed in standard locations (e.g., R and Ctr) with a ground electrode placed elsewhere on the head. The voltage measured between the well-separated sensing electrodes is the far-field dominant (i.e., EEG-dominant) channel. Additional electrodes are placed near each of the two sensing electrodes. (The additional electrodes are immediately lateral to the existing electrodes in the horizontal array, and are immediately above the existing electrodes in the vertical array.) The voltages measured between the pairs of closely spaced electrodes are near-field dominant (i.e., EMG/EOG-dominant) channels.

Abstract: A catheter system comprising a delivery catheter and an inner catheter, wherein the inner catheter is deployable and has a plurality of electrodes on the lattices of a trellis fixture. During a deployed state, the trellis fixture is fully extended to have a series of electrodes on a two-dimensional plane for mapping and/or ablation purposes.

Abstract: A visually-positioned electrical monitoring apparatus includes an electrical assembly comprising an elongate, flaccid dielectric body having at least one electrical contact, a passage and an open distal end. An endoscope extends through the passage and has its distal end substantially in registry with the distal end of the body. A method for placing an electrical monitoring assembly to coact with human tissue at a target site includes providing the aforedescribed monitoring assembly, extending an endoscope into the passage, aligning the distal end of the endoscope with the distal end of the body and visually guiding the assembly to the site.

Abstract: A universal disposable ECG sensor positioning device and method for use with electrocardiogram diagnostic equipment in which the mask has nine sensors, six of which can be used at any one time to provide three different sizes to accommodate varying sized human torsos.

Abstract: An electrode array for collecting surface electromyographic (EMG) signals from a patient consists of 63 electrically conductive electrodes supported in a non-conductive, flexible pad in a predetermined pattern of nine rows and seven columns of equally spaced electrodes. The flexible pad allows the electrode array to conform to the external curvature of the patient, while the 9.times.7 rectangular array of electrodes provides a unique pattern related to the configuration of underlying muscle groups of the patient. This allows the sensor pad to be uniquely positioned relative to the patient's anatomy and to provide signals representative of the muscle activity, which can then be electronically displayed in a corresponding pattern, for evaluation by the attending physician.

Abstract: The connection element for an outer end piece of a surgical electrode is provided for application for the surface of the body of a heart patient. It provides a mechanical and an electrical connection between the outer end piece and a connection socket. It is advantageous to use one or a plurality of electrodes for the temporary monitoring and/or stimulation of the heart activity. One indifferent electrode arranged on the surface of the body, which is preferably mounted on a baseplate of the connection element, is associated with the or each unipolar electrode.

Abstract: A precordial overlay is configured for precise electrode placement on a patient as part of an electrocardiographic test. It is especially useful by emergency medical personnel who are often called upon to obtain an ECG. The precordial overlay has an elongated band having a first generally rectangular-shaped section, a second generally rectangular-shaped and an intermediate section connecting the first and second sections. Electrodes are slidably mounted in the three sections to allow for limited but quick movement from an approximate chest area location to a precise chest area location for a reliable electrocardiographic test.

Abstract: The invention provides a sealed package system for housing at least two medical electrode devices and for enabling the periodic testing thereof, comprising a thin, generally flat flexible envelope constructed and arranged to form an interior cavity for enclosing a conductive gel contact surface of each of the electrode devices. A conductive liner is disposed between conductive gel contact surface of each of the electrode devices.

Abstract: A medical extravasation device has an electrode patch that can attach to the skin for sensing electrical information. Tissue impedance is calculated from the electrode patch signals. The patch has elongate pick-up electrodes inboard of elongate energizing electrodes. The measuring zone determined by the elongate space between the pick-up electrodes enhances sensitivity and specificity. The presence of an extravasation is determined by interpreting the tissue impedance measurement. The method for determining the extravasation includes a first step of determining a pre-injection baseline measurement of the tissue impedance. Then, the tissue impedance is monitored during the procedure itself. A predetermined amount of change in tissue impedance is determined to indicate an extravasation.

Abstract: A medical electrical lead for establishing an electrical connection with a tissue of the body, the lead having a lead body and a semi-cylindrical cuff. In the preferred embodiment the semi-cylindrical cuff features one or more electrodes. The semi-cylindrical cuff having a long flap which wraps about the cuff and a short flap which wraps about the long flap. The semi-cylindrical cuff is relatively stiff as compared to the short flap. The short flap, in turn, is relatively the same stiffness as the long flap. The stiffness of each flap may be varied, however, so that one is more or less than the other, and in turn, than the cuff. Through such a multi-flap construction the electrodes may be positioned proximal to a nerve in such a manner that the mechanically induced damage may be minimized or even entirely eliminated. Finally, a method of implanting such an electrode is also disclosed.

Abstract: A bioelectric interface is disclosed which provides three Einthoven triangle equivalent lead forming electrodes positioned on a subject's chest so as to provide a Wilson common terminal voltage essentially equivalent to that provided by an Einthoven triangle formed using leads positioned conventionally on a subject's limbs. Wilson common terminal forming resistors can be of fixed values or variable to allow adjustment of a produced Wilson common terminal voltage. Additional precordial electrodes are also typiclaly present. Electrodes can consist of single elements or groups of electrode elements, and are present in locational regions of the bioelectric interface which allow a single size system to fit to patients with various sized bodies. The electrodes can be of various physical shapes to allow not only direct signal measurement, but also to allow monitoring of high frequency content of signals and to allow enhanced resolution of a region from which measured signals originate.

Abstract: Apparatus and methods are provided for performing an in situ characterization of a tissue mass which may be normal, malignant, or benign, and, based on the measured characteristics of the tissue mass, therapeutically treating the tissue mass to cause necrosis of the tissue. In an illustrative preferred embodiment, the characterization of the tissue is accomplished by measuring an electrical property of the tissue, such as electrical impedance, while treatment is accomplished by supplying heat to the tissue to induce cauterization.

Abstract: An implantable electrical lead having an elongated lead body carrying a conductor therein and an elongated electrode extending from the lead body and coupled to the conductor. The lead is provided with an insulative tubular sheath mounted around the electrode and slideable thereon, the sheath having a length less than that of the electrode. Optionally, the sheath is provided with a mechanism for facilitating its removal from the electrode, which may take the form of a weakened zone formed in the sheath. The lead may be provided with a plurality of insulative sheaths slidably mounted around the electrode, and each sheath is preferably provided with a mechanism for stabilizing the location of the sheath along the electrode, which mechanism may function to frictionally engage the sheath with the electrode or to compress the sheath around the electrode.

Abstract: An electro-dermal connector device includes a flexible non-conductive sheet and electrode sensors V.sub.1 to V.sub.6 disposed on the non-conductive sheet in a dimensional array and adapted for electrical connection with the skin for receiving and transmitting electrical impulses. On the non-conductive sheet the distance between electrodes V.sub.1 and V.sub.2 is 2.00 inches .+-.0.56 inches, and the distance between V.sub.2 and V.sub.4 is about 3.5 inches .+-.1.00 inch, with V.sub.3 located substantially midway between V.sub.2 and V.sub.4 and V.sub.5 is generally equidistant between V.sub.4 and V.sub.6.

Abstract: A transcutaneous medical electrode includes a highly conductive grid, having a plurality of arrays of electrical conductors, for controlling current distribution of directed electrical pulses. Electrical connectors are provided for establishing electrical communication with the conductive grid for enabling selective electrification of the electrical conductors in each array. The conductive grid is supported by a moderately conductive sheet, or film, and a conductive adhesive is provided for removably coupling the sheet or film and the conductive grid to a user's body.

Abstract: An improved tissue electrode for monitoring tissue electrical activity and for tissue electrical stimulation and adapted to conform closely to the tissue, thereby optimizing tissue electrical contact. The electrode consists of an elongated electrode body with a polygonal cross-section with a tissue-engaging surface having a pair of tissue-engaging members confronting each other at an obtuse angle and a non-tissue-engaging surface meeting each of the tissue-engaging members at an acute angle. In one embodiment, the non-tissue-engaging surface is substantially flat, and the electrode thus is a half-rhombus in cross-section. In a second embodiment, the non-tissue-engaging surface is also a half-rhombus, so that the electrode is a rhombus in cross-section. An improved electrical connector for connecting lead wires from the electrode to external monitoring equipment is also disclosed.

Abstract: An over-the-wire electrophysiology catheter which has an emitting electrode on the distal tip electrically connected to a source of high frequency electrical energy. The intravascular device is configured to be advanced through a patient's cardiac veins or coronary arteries and preferably is also provided with sensing electrodes for detecting electrical activity of the patient's heart from within a blood vessel of the heart. The device forms large lesions in tissue adjacent to the blood vessel in which the device is located without significantly damaging the blood vessel to effectively terminate signals causing arrhythmia.

Abstract: A harness for placing on a patient's chest allows ECG measurements to be quickly made. The harness includes a strip of nonconductive film having a connector terminal at one edge for connection to an ECG measuring devise. The strip has a number of electrodes formed on it, each having leads extending to the connector terminal. At least some of the electrodes are grouped into sets. Each of the sets has a pattern of electrodes spaced for placement on a patient of a different size. Each of the electrodes within the sets has a corresponding electrode in another of the sets with which it is in electrical common. A backing layer may be peeled-off to expose the electrodes. The backing layer has separate zones, one for each of the sets of electrodes.

Abstract: A template has a flexible sheet with a fixed dimensional array V.sub.1 -V.sub.6 positioned in a specific size configuration appropriate for standard electrocardiographic recording. The distance between V.sub.1 and V.sub.2 is 2.00 inches.+-.0.56 inches, and the distance between V.sub.2 and V.sub.4 is 3.5 inches.+-.1.00 inch, with V.sub.3 located substantially midway between V.sub.2 and V.sub.4, and V.sub.5 is equidistant between V.sub.4 and V.sub.6.

Abstract: The invention relates to an electrodeless device for administering an electrocardiogram consisting essentially of a single flexible sheet having multiple electrical strips or wires pre-positioned for placement on a patient's chest. The device includes at least two positioning means.

Abstract: A catheter having an elongated polymeric body with hollow encircling ring electrodes thereon and a method of forming the same are provided by the invention. Ring electrodes are each connected to an external electrical circuit by wires extending through the lumen, the wires each passing through an aperture through a wall of the body and being connected to an interior surface of the ring electrode. The tubular body of the catheter is expanded into a tight interference fit with the interior surfaces of the ring electrodes by heating the body to a temperature approaching its glass transition temperature to permit relief of internal stresses.

Abstract: An intraventricular multielectrode cardiac mapping probe having an electrode array assembly which is initially stored within the distal lumen of a delivery catheter and after placement of the tip of the catheter at a target location within the heart the electrode array may be moved out of its retracted position to expand into a generally planar configuration to position electrodes for mapping of the heart chamber.

Abstract: A gauging esophageal catheter or stethoscope which is insertable into the esophagus or stomach of a subject or patient, has an elongated, flexible body portion having an instrument carried on a distal end. The catheter has a series of user visible gradations for permitting selective positioning of the instrument at a predetermined insertion depth within the subject. The gradations are calibrated to the height, weight or body surface area of the subject. The gradations may be printed on the body portion, or the body portion may have a transparent portion, and the gradations may be carried on a member internal thereto which is visible through the transparent portion.

Abstract: Apparatus and methods are provided for mapping an interior surface of a section of a body lumen comprising a catheter having a plurality of elements circumferentially disposed around its distal end that contact the interior surface of a body lumen and provide output signals corresponding to the local diameter of the lumen. In a preferred embodiment, the contacts are of an electrical-mechanical type, such that an output signal may be generated which is proportional to the degree of deflection of the contact caused by the local diameter of the body lumen. The distal end of the catheter is translated through the body lumen for a predetermined distance, while the output signals are reproduced on either an analog recorder or as a digital three-dimensional display. A drive system for translating the catheter, and methods of use, are also provided.

Abstract: A portable EKG machine having a plurality of individually storable electrode leads, each of which may be selectively moved from a retracted position wherein the electrode lead is stored within a storage enclosure, to an extended position wherein the electrode lead is drawn from the storage enclosure. The EKG machine of the present invention includes a monitor, a storage enclosure and a plurality of conducting leads each terminating in an electrode. In a preferred embodiment, the storage enclosure includes a plurality of retractable and extendable leads mounted on individual rotatable spools enclosed therein. Each electrode and lead may be individually selectively extended by an EKG technician by grasping and separating an electrode from the storage enclosure thereby unwinding the lead from its storage spool to an extended position, whereafter the electrode may be conductively attached to the patient's body.

Abstract: An ECG harness is positioned on the chest of patient for making electrocardiographic measurements. The harness includes a strip of nonconductive film having a plurality of slots spaced along the length of the strip at selected anatomical positions. A connector terminal is formed at one edge of the strip for connection to a monitoring device. Electrically conductive border traces extend around the slots. The border traces are exposed on the outer side of the strip and insulated from the inner side of the strip. Conductive leads extend from the connector terminal to the border traces. Electrode pads are placed on the outer side of the strip at least partially extending over the slots. Each of the electrode pads has a conductive inner side for electrical contact with one of the border traces and the skin of the patient.

Abstract: An electrode assembly adapted to be attached to the skin over selected facial muscle groups picks up signals to be analyzed by an anesthesia adequacy monitor that measures the level of awareness of a living animal, typically a human being. Also disclosed is a method of manufacturing the electrode assembly by printing a pattern of electrically conductive material through a silk-screen onto a flexible layer, and then coating the result with a non-conducting adhesive except at points corresponding to sensing points for the desired muscle groups. Finally, a method for using such sensing means is shown in maintaining an appropriate level of patient awareness under anesthesia.